Glossary of terms
This glossary lays out all of the key terms YOU may come across while using cheqd.
A service provider that hosts Cloud Agents and may provision Edge Agents on behalf of Entities. Agencies may be Unaccredited, Self-Certified, or Accredited.
A software program or process used by or acting on behalf of an Entity to interact with other Agents or with the cheqd Network or other distributed ledgers. Agents are of two types: Edge Agents run at the edge of the network on a local device; Cloud Agents run remotely on a server or cloud hosting service. Agents require access to a Wallet in order to perform cryptographic operations on behalf of the Entity they represent.
Agent-to-Agent (A2A) Protocol
A protocol for communicating between Agents to form Connections, exchange Credentials, and have other secure private Interactions. A less technical synonym is DID Communication (DIDComm).
Agent-to-Agent (A2A) Protocol Layer
The technical stack 'Layer' for peer-to-peer Connections and Interactions over the Agent-to-Agent Protocol.
A DID used exactly once, so it cannot be contextualized or correlated beyond that single usage. See also Pseudonym and Verinym.
A non-reciprocal relationship rooted in the Identity of one party, where the other party is the public (a faceless “other” that can be instantiated without bound). For an Organization to issue publicly Verifiable Credentials, its Issuer DID must be on a public ledger such as cheqd. It is thus an Anywise DID—a DID to which any other Entity may refer without coordination. The term “public DID” is sometimes used as a casual synonym for “Anywise DID”. However, “public DID” is deprecated because it is ambiguous, i.e., it may refer to a DID that is world-visible but usable only in pairwise mode, or to a DID that is not published in a central location but nonetheless used in many contexts, or to a DID that is both publicly visible and used in Anywise mode. Compare N-wise and Pairwise.
The exchange token that runs and transacts natively on the Cosmos ledger.
An Identity trait, property, or quality of an Entity.
A relatively new term, intended to replace 'Self-sovereign identity'. It relates to signed, verifiable and cryptographically resolvable data using the W3C Verifiable Credential data model.
A type of cryptocurrency, famously created by pseudonymous Satoshi Nakamoto, using a Proof-of-Work (PoW) consensus model to mine blocks.
A set of transaction data, forming part of a Blockchain.
A system in which a record of transactions are maintained across several computers that are linked in a distributed, peer-to-peer network.
Attaching tokens to a specific Node Operator, to participate in cheqd Network Governance and delegate unused votes to that specific Node Operator.
The native medium of exchange, governance and transaction fees on the cheqd Network.
The blockchain, built on the Cosmos SDK, that cheqd uses for transactions, governance and identity interactions.
An assertion about an Attribute of a Subject. Examples of a Claim include date of birth, height, government ID number, or postal address—all of which are possible Attributes of an Individual. A Credential is comprised of a set of Claims. (Note: Early in the development of Self-Sovereign Identity technology, this term was used the same way it was used in the early W3C Verifiable Claims Working Group specifications—as a synonym for what is now a Credential. That usage is now deprecated.)
An Agent that is hosted in the cloud. It typically operates on a computing device over which the Identity Owner does not have direct physical control or access. Mutually exclusive with Edge Agent. A Cloud Agent requires a Wallet and typically has a Service Endpoint. Cloud agents may be hosted by an Agency.
A coin operates on its own independent blockchain and acts like a native currency within a specific financial system.
A cryptographically verifiable communications channel established using an Agent-to-Agent Protocol between two DIDs representing two Entities and their associated Agents. Connections may be Edge-to-Edge Connections or Cloud-to-Cloud Connections. Connections may be used to exchange Verifiable Credentials or for any other communications purpose. Connections may be encrypted and decrypted using the Public Keys and Private Keys for each DID. A Connection may be temporary or it may last as long as the two Entities desire to keep it. Two Entities may have multiple Connections between them, however each Connection must be between a unique pair of DIDs. A relationship between more than two Entities may be modeled either as Pairwise connections between all of the Entities (Peering) or each Entity can form a Connection with an Entity representing a Group.
An Agent-to-Agent Protocol message type sent from one Entity to a second Entity to invite the second Entity to send a Connection Request.
A subdocument of a Governance Framework as a normative component of the framework. These are often referred to in the Trust over IP metamodel, which cheqd intends to comply with.
An Entity that has the Private Keys and responsibility to take actions on behalf of another Entity.
The distributed ledger, with the coin ATOM, which cheqd is building its infrastructure on top of.
The development kit that cheqd is using to build its infrastructure.
The Principles published in this Governance Framework that seek to govern the behaviour of participants in the cheqd Network.
A digital assertion containing a set of Claims made by an Entity about itself or another Entity. Credentials are a subset of Identity Data. A Credential is based on a Credential Definition.
Once issued, a Credential is typically stored by an Agent. (In cheqd's infrastructure, Credentials are never stored on the Ledger.) Credentials are very broad in their potential use: Examples of Credentials include college transcripts, driver licenses, health insurance cards, and building permits. See also Verifiable Credential.
Credential Definition (CredDef)
A machine-readable definition of the semantic structure of a Credential based on one or more Schemas. Credential Definitions are stored on the cheqd Network. Credential Definitions must include an Issuer Public Key. Credential Definitions facilitate interoperability of Credentials and Proofs across multiple Issuers, Holders, and Verifiers.
A set of Interaction Patterns within an Agent-to-Agent Protocol for exchange of Credentials between Entities acting in Credential Exchange Roles.
Credential Exchange Layer
The technical infrastructure Layer for Credential Exchange.
An Agent-to-Agent Protocol message type sent from an Issuer to a Holder to invite the Holder to send a Credential Request to the Issuer.
An Entity that serves as a Holder of Credentials issued by Trust Community Members in order to provide a cryptographically verifiable directory service to the Trust Community or to the public. The term also refers to the actual repository of Credentials maintained by this Entity. An informal Credential Registry may accept Credentials from participants whose purpose is to cross-certify each other’s roles in the Trust Community. A formal Credential Registry may be authorized directly by a Governance Authority or Accredited by an authorized Auditor for the relevant Governance Framework.
An Agent-to-Agent Protocol message type sent from a Holder to an Issuer to request the issuance of a Credential to that Holder.
A digital currency in which transactions are verified and records maintained by a decentralized system using cryptography, rather than by a centralized authority.
Trust bestowed in a set of machines (Man-Made Things) that are operating a set of cryptographic algorithms will behave as expected. This form of trust is based in mathematics and computer hardware/software engineering. Compare with Human Trust.
As defined by the EU General Data Protection Regulation (GDPR), the natural or legal person, public authority, agency, or other body which, alone or jointly with others, determines the purposes and means of the processing of Personal Data.
As defined by the EU General Data Protection Regulation (GDPR), a natural or legal person, public authority, agency, or other body which processes Personal Data on behalf of a Data Controller.
Data Protection by Design
A widely recognized set of principles for protecting Personal Data. Specific cheqd Data Protection by Design principles are a subset of the General Principles in the cheqd Governance Framework.
As defined by the EU General Data Protection Regulation (GDPR), any person whose Personal Data is being collected, held, or processed. In the cheqd Governance Framework, a Data Subject is referred to as an Individual.
Synonymous with Self-Sovereign Identity, decentralised identity refers to the control and management of identity Credentials, Claims and Attributes by an Entity which the data contained in the Credentials, Claims and Attributes is about.
Decentralised Identifier (DID)
A globally unique identifier developed specifically for decentralized systems as defined by the W3C DID specification. DIDs enable interoperable decentralized Self-Sovereign Identity management. A DID is associated with exactly one DID Document.
This term has two meanings in different contexts. Firstly, it can mean an Identity Controller that acts on behalf of another Identity Controller to assist or manage Credentials, Claims or Attributes on behalf of that secondary Identity Controller.
Secondly, it can mean delegating tokens for the purpose of participating in cheqd on-chain Governance. Delegating tokens means bonding tokens to a specific Node Operator.
Acronym for Decentralized Identifier.
Synonym for Agent-to-Agent Protocol.
The machine-readable document to which a DID points as defined by the W3C DID specification. A DID document describes the Public Keys, Service Endpoints, and other metadata associated with a DID. A DID Document is associated with exactly one DID.
A specification that defines a particular type of DID conforming to the W3C DID specification. A DID Method specifies both the format of the particular type of DID as well as the set of operations for creating, reading, updating, and deleting (revoking) it.
A software module that takes a DID as input and returns a DID document by invoking the DID Method used by that particular DID. Analogous to the function of a DNS resolver.
The Entity identified by a DID.
Decentralized Key Management System, an emerging standard for interoperable cryptographic key management based on DIDs.
A subset of the Agent-to-Agent Protocol that enables Agents to perform DKMS functions for interoperable digital Wallet management, e.g., key exchange, automated backup, offline recovery, social recovery, etc.
An Agent that operates at the edge of the network on a local device, such as a smartphone, tablet, laptop, automotive computer, etc. The device owner usually has local access to the device and can exert control over its use and authorization. Mutually exclusive with Cloud Agent. An Edge Agent may be an app used directly by an Identity Owner, or it may be an operating system module or background process called by other apps. Edge Agents typically do not have a publicly exposed Service Endpoint in a DID Document, but do have access to a Wallet. Note that the local device may itself be an Active Thing with its own Agent, and for which the Identity Owner is the Thing Controller.
A Connection that forms and/or communicates directly between two Edge Agents.
As used in IETF RFC 3986, Uniform Resource Identifier (URI), a resource of any kind that can be uniquely and independently identified.
The determinate and irreversible transition of the cheqd Network’s application of Governance from centralisation to decentralisation.
A proportion of Network transaction costs that is taken used to remunerate Network participants or the Community Pool.
Gas refers to the fee, or pricing value, required to successfully conduct a transaction or execute a contract on a blockchain.
The initial Network parameters governing how cheqd works at an architectural level.
Governance is a way of regulating behaviour and ensuring order in a given system. We think of it as a melting pot with Principles, Laws, Economics and System Design as the ingredients.
Governance Authority (GA)
The Entity (typically an Organization) governing and making decisions related to a particular Governance Framework. cheqd does not have a Governance Authority in its traditional sense, its governance is conducted by the distributed consensus of the Network itself.
An Identity Controller who administers Identity Data, Wallets, and/or Agents on behalf of a Dependent. A Guardian is different than a Delegate—in Delegation, the Identity Controller still retains control of one or more Wallets. With Guardianship, an Identity Controller is wholly dependent on the Guardian to manage the Identity Controllers' Wallet.
A role played by an Entity when it is issued a Credential by an Issuer. The Holder may or may not be the Subject of the Credential. (There are many use cases in which the Holder is not the Subject, e.g., a birth certificate where the Subject is a baby and both the mother and father may be Holders.) Holders are also those who own and hold CHEQ.
An initiative of the Linux Foundation to develop open source distributed ledger and blockchain technology. The Hyperledger home page is https://wiki.hyperledger.org/.
Provides a shared, reusable, interoperable tool kit designed for initiatives and solutions focused on creating, transmitting and storing verifiable digital credentials. It is infrastructure for blockchain-rooted, peer-to-peer interactions.
An open source project under the Hyperledger umbrella for decentralized Self-Sovereign Identity. The source code for Hyperledger Indy was originally contributed to the Linux Foundation by the Sovrin Foundation. cheqd does not use Hyperledger Indy for its Network, instead it uses Cosmos.
A shared cryptographic library that would enable people (and projects) to avoid duplicating other cryptographic work and hopefully increase security in the process.
A text string or other atomic data structure used to provide a base level of Identity for an Entity in a specific context. In Self-Sovereign Identity systems, Decentralized Identifiers (DIDs) are the standard Identifier.
The set of data associated with an Identity that permits identification of the underlying Entity.
The person, organisation, group or thing that retains control over the Private Key(s) relating to specific identity data.
A set of messages exchanged over a Connection using an Agent-to-Agent Protocol.
The Entity that issues a Credential to a Holder. Based on the definition provided by the W3C Verifiable Claims Working Group.
Open standard data format used for some Verifiable Credentials
Open standard data format used for some Verifiable Credentials, specifically for linking data to other datasets.
The process of recovering access to and control of a set of Private Keys—or an entire Wallet—after loss or compromise. Key Recovery is a major focus of the emerging DKMS standard for cryptographic key management.
The core, foundational infrastructure that an SSI ecosystem is built upon. In cheqd's case, the cheqd Network is Layer 1.
Within blockchains a Layer 2 is a separate ledger running adjacent to the Layer 1. Layer 2 Networks are used for efficiency and scaling. The outcome of Layer 2 transactions and interactions are recorded periodically back into Layer 1.
Level of Assurance (LOA)
A measure, usually numeric, of the Trust Assurance that one Entity has in another Entity based on a defined set of criteria that establish the amount of reliance the first Entity may accept from the second Entity in the performance of the criteria. LOAs are often defined in or referenced by Governance Frameworks.
Pools of tokens locked in smart contracts that provide liquidity in decentralized exchanges in an attempt to attenuate the problems caused by the illiquidity typical of such systems.
cheqd's Network has both a test net and a main net. The main net is the Network where live and public transactions will take place after launch.
The minimum amount of tokens needed for a governance proposal to reach the stage where it is voted upon.
Minting a token simply means creating a token on-ledger
A computer network server running an instance of the code necessary to operate a distributed ledger or blockchain. In cheqd Infrastructure, a Node is operated by a Node Operator running an instance of the cheqd Open Source Code.
The Entity responsible for running a node.
A governance model in which the Governance Authority is open to public participation, operates with full transparency, and does not favor any particular contributor or constituency.
Open Source License
Technical standards that are developed under an Open Governance process; are publicly available for anyone to use; and which do not lock in users of the standard to a specific vendor or implementation. Open Standards facilitate interoperability and data exchange among different products or services and are intended for widespread adoption. Many Open Standards have implementations that are available under an Open Source License.
A legal Entity that is not a natural person (i.e., not an Individual). Examples of Organizations include a Group, sole proprietorship, partnership, corporation, LLC, association, NGO, cooperative, government, etc. Mutually exclusive with Individual.
A data structure that provides an extra layer of contextual and/or conditional information to a Schema. This extra context can be used by an Agent to transform how information is displayed to a viewer or to guide the Agent in how to apply a custom process to Schema data.
A direct relationship between exactly two Entities. Most relationships in the cheqd ecosystem will be likely Pairwise, even when one or both Entities are not Individuals. For example, business-to-business relationships are pairwise by default. A DID or a Public Key or a Service Endpoint is Pairwise if it is used exclusively in a Pairwise relationship. Pairwise relationships can exist entirely off-ledger.
A transfer of CHEQ or other cryptographically verifiable units of value from one Entity to another Entity.
The address of a Payment Transaction on the cheqd Network.
Permissionless blockchains are blockchains that require no permission to join and interact with.
As defined by the EU General Data Protection Regulation (GDPR), any information relating to an identified or identifiable natural person. In the GDPR, this natural person is called the Data Subject. Personal data SHOULD never be written to the cheqd Network.
Privacy by Design
A set of seven foundational principles for taking privacy into account throughout the entire design and engineering of a system, product, or service. Originally defined by the Information and Privacy Commissioner of Ontario, Canada.
The half of a cryptographic key pair designed to be kept as the Private Data of an Entity. In elliptic curve cryptography, a Private Key is called a signing key.
Cryptographic verification of a Claim or a Credential. A digital signature is a simple form of Proof. A cryptographic hash is also a form of Proof. Zero Knowledge Proofs enable selective disclosure of the information in a Credential.
The data structure sent by a Verifier to a Holder that describes the Proof required by the Verifier.
A DID used to prevent correlation outside of a specific context. A Pseudonym may be Pairwise, N-wise, or Anywise.
The half of a cryptographic key pair designed to be shared with other parties in order to decrypt or verify encrypted communications from an Entity. In digital signature schemes, a Public Key is also called a verification key. A Public Key may be either Public Data or Private Data depending on the policies of the Entity.
The minimum number of participants in the Network who need to vote on a governance proposal for the vote to be valid.
A special Private Key used for purposes of recovering a Wallet after loss or compromise. In the DKMS key management protocol, a Recovery Key may be cryptographically sharded for secret sharing.
Recovery Key Trustee
A Trustee trusted by another Identity Controller to authorise sharing back a Recovery Key for purposes of restoring a Wallet after loss or compromise.
An Entity that consumes Identity Data and accepts some Level of Assurance from another Entity for some purpose. Verifiers are one type of Relying Party.
A software module that accepts an Identifier as input, looks up the Identifier in a database or ledger, and returns metadata describing the identified Entity. The Domain Name System (DNS) uses a DNS resolver. Self-Sovereign Identity uses a DID Resolver.
The act of an Issuer revoking the validity of a Claim or a Credential.
An online repository of data needed for Revocation. In cheqd's Network Infrastructure, a Revocation Registry is a privacy-respecting cryptographic data structure maintained on the Ledger by an Issuer in order to support Revocation of a Credential.
A machine-readable definition of the semantics of a data structure. Schemas are used to define the Attributes used in one or more Credential Definitions.
Security by Design
A widely recognized set of principles for building security into systems, products, and services from the very start.
A Privacy by Design principle of revealing only the subset of the data described in a Claim, Credential, or other set of Private Data that is required by a Verifier.
Self-Sovereign Identity (SSI)
An identity system architecture based on the core principle that individual Identity Controllers have the right to permanently control one or more Identifiers together with the usage of the associated Identity Data.
An addressable network location offering a service operated on behalf of an Entity. As defined in the DID specification, a Service Endpoint is expressed as a URI (Uniform Resource Identifier).
The potential deduction of tokens for bad behaviour on the Network.
A general representation of different technological functions and protocols that provide different functions on top of each other. The most common SSI stack is the Trust over IP stack.
In order to participate in cheqd Network governance, participants must allocate a proportion of their tokens to float on the Network. Staking is required to validate transactions and earn Staking rewards.
The point at which the cheqd Network is spread amongst enough nodes that no one node is directly accountable for decisions on the Network. This is reached through the increasing of Entropy.
A medium of interaction, either for pure utility or for payment transactions.
The fundamental code and parameters that determines how the Network architecture runs.
A mark associated with a Transaction to suggest that the Transaction should no longer be returned in response to requests for read access.
A record of any type written to the cheqd Network.
A Credential that includes a Proof from the Issuer. Typically this proof is in the form of a digital signature.
An Entity who requests a Credential or Proof from a Holder and verifies it in order to make a trust decision about an Entity.
A DID that it is directly or indirectly associated with the Legal Identity of the Identity Controller.
A software module, and optionally an associated hardware module, for securely storing and accessing Private Keys other sensitive cryptographic key material, and other Private Data used by an Entity. A Wallet is accessed by an Agent.
Zero Knowledge Proof
A Proof that uses cryptography to support Selective Disclosure of information about a set of Claims from a set of Credentials. A Zero Knowledge Proof provides cryptographic proof about some or all of the data in a set of Credentials without revealing the actual data or any additional information, including the Identity of the Holder.